Alert archive / Massachusetts / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 103, NWS Boston/Norton, MA

August 18, 2011Middlesex County, Worcester County, Massachusetts; Cheshire County, Hillsborough County, New Hampshire

NWS Boston/Norton, MA issued this severe thunderstorm warning at Aug 18, 2011, 7:30 PM EDT for Middlesex County, Worcester County, Massachusetts; Cheshire County, Hillsborough County, New Hampshire. It was in force for 60 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 18, 2011, 7:30 PM EDT (23:30 UTC)
Expired
Aug 18, 2011, 8:30 PM EDT
In force
60 min
Issued by
NWS Boston/Norton, MA
Area
Storm-based polygon

Counties Middlesex County, MA, Worcester County, MA, Cheshire County, NH, Hillsborough County, NH

The radar

The Boston radar (KBOX), 105 km from the middle of the area, began a volume at 23:33 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Albany, NY (KALY), launched 12:00Z, 11.5 hours before the alert went out and 163 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Albany, NY at 12:00Z on 2011-08-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 130 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Albany, NY at 12:00Z on 2011-08-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 96 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
130 J/kg
Mixed-layer CIN
-115 J/kg
Mixed-layer LCL
1201 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
96 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

727 
WUUS51 KBOX 182330
SVRBOX
MAC017-027-NHC005-011-190030-
/O.NEW.KBOX.SV.W.0103.110818T2330Z-110819T0030Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TAUNTON MA
730 PM EDT THU AUG 18 2011

THE NATIONAL WEATHER SERVICE IN TAUNTON HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTH CENTRAL WORCESTER COUNTY IN CENTRAL MASSACHUSETTS...
  NORTHWESTERN MIDDLESEX COUNTY IN SOUTHEAST MASSACHUSETTS...
  SOUTHEASTERN CHESHIRE COUNTY IN SOUTHERN NEW HAMPSHIRE...
  SOUTH CENTRAL HILLSBOROUGH COUNTY IN SOUTHERN NEW HAMPSHIRE...

* UNTIL 830 PM EDT

* AT 728 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  WINCHENDON...OR 9 MILES SOUTH OF JAFFREY...AND WAS MOVING EAST AT
  10 MPH.

* SOME LOCATIONS IN THE WARNING INCLUDE...ASHBURNHAM...SHARON...NEW
  IPSWICH...TEMPLE...ASHBY...GREENVILLE...MASON...LUNENBURG AND
  TOWNSEND.

SEVERE THUNDERSTORMS PRODUCE DAMAGING WINDS AND LARGE HAIL...AS WELL
AS DEADLY LIGHTNING AND TORRENTIAL RAIN. GET TO SAFE SHELTER NOW...
INSIDE A STURDY BUILDING OR IN A VEHICLE. DO NOT SEEK SHELTER UNDER
TREES. IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE STRUCK BY
LIGHTNING. DRIVERS SHOULD BE ALERT FOR PONDING OF WATER AND AVOID
FLOODED ROADS.

&&

LAT...LON 4285 7168 4259 7166 4263 7208 4279 7207
TIME...MOT...LOC 2330Z 270DEG 10KT 4269 7196

$$

DUNTEN
3 follow-up statements
415 
WWUS51 KBOX 182354
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
754 PM EDT THU AUG 18 2011

NHC005-190004-
/O.CAN.KBOX.SV.W.0103.000000T0000Z-110819T0030Z/
CHESHIRE NH-
754 PM EDT THU AUG 18 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN CHESHIRE COUNTY
IS CANCELLED...

LAT...LON 4259 7166 4263 7199 4271 7198 4271 7193
      4279 7194 4279 7196 4280 7195 4285 7168
TIME...MOT...LOC 2354Z 287DEG 16KT 4266 7185

$$

MAC017-027-NHC011-190030-
/O.CON.KBOX.SV.W.0103.000000T0000Z-110819T0030Z/
MIDDLESEX MA-WORCESTER MA-HILLSBOROUGH NH-
754 PM EDT THU AUG 18 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM EDT
FOR SOUTH CENTRAL HILLSBOROUGH...NORTH CENTRAL WORCESTER AND
NORTHWESTERN MIDDLESEX COUNTIES...

AT 750 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR ASHBURNHAM...OR 6 MILES NORTHWEST OF FITCHBURG...MOVING
EAST AT 15 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
ASHBY...MASON AND TOWNSEND

LAT...LON 4259 7166 4263 7199 4271 7198 4271 7193
      4279 7194 4279 7196 4280 7195 4285 7168
TIME...MOT...LOC 2354Z 287DEG 16KT 4266 7185

$$

DUNTEN
217 
WWUS51 KBOX 190013
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
813 PM EDT THU AUG 18 2011

NHC011-190023-
/O.CAN.KBOX.SV.W.0103.000000T0000Z-110819T0030Z/
HILLSBOROUGH NH-
813 PM EDT THU AUG 18 2011

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL HILLSBOROUGH
COUNTY IS CANCELLED...

LAT...LON 4271 7169 4270 7167 4259 7166 4262 7191
      4271 7185
TIME...MOT...LOC 0013Z 294DEG 13KT 4263 7178

$$

MAC017-027-190030-
/O.CON.KBOX.SV.W.0103.000000T0000Z-110819T0030Z/
MIDDLESEX MA-WORCESTER MA-
813 PM EDT THU AUG 18 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 830 PM EDT
FOR NORTH CENTRAL WORCESTER AND NORTHWESTERN MIDDLESEX COUNTIES...

AT 811 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING PENNY SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR ASHBY...OR NEAR FITCHBURG...MOVING SOUTHEAST AT 15 MPH.

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO
TOWNSEND

LAT...LON 4271 7169 4270 7167 4259 7166 4262 7191
      4271 7185
TIME...MOT...LOC 0013Z 294DEG 13KT 4263 7178

$$

DUNTEN
108 
WWUS51 KBOX 190026
SVSBOX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TAUNTON MA
826 PM EDT THU AUG 18 2011

MAC017-027-190037-
/O.EXP.KBOX.SV.W.0103.000000T0000Z-110819T0030Z/
MIDDLESEX MA-WORCESTER MA-
826 PM EDT THU AUG 18 2011

...THE SEVERE THUNDERSTORM WARNING FOR NORTH CENTRAL WORCESTER AND
NORTHWESTERN MIDDLESEX COUNTIES WILL EXPIRE AT 830 PM EDT...

LAT...LON 4271 7169 4270 7167 4259 7166 4262 7191
      4271 7185
TIME...MOT...LOC 0027Z 283DEG 12KT 4262 7173

$$

DUNTEN

The office that day

Everything else NWS Boston/Norton, MA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 18, 6:24 PM EDTSpecial Weather StatementBOXHampden36 min
Aug 18, 7:50 PM EDTAreal Flood AdvisoryBOXMiddlesex, Worcester2 hr
Aug 18, 5:46 PM EDTSpecial Weather StatementBOXCheshire44 min
Aug 18, 6:39 PM EDTSpecial Weather StatementBOXCheshire51 min
Aug 18, 7:26 PM EDTSpecial Weather StatementBOXHillsborough49 min

Nearby

Severe Thunderstorm Warnings in Massachusetts, 2011Severe Thunderstorm Warnings in New Hampshire, 2011Every severe thunderstorm warning in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.